history
Questions?
ISP
Go back to last week's notes, talk about geekstorage
new web page stuff
New tags?
New CSS ?
networks
bandwith
See
units
- bit/sec = bit/s = bps
- Byte/sec = Byte/s = Bps = 8 bit/s = 8 char/sec
- kB = kiloByte = 1,000 Byte = 10^3 Byte
- MB = MegaByte = 1,0000,000 Byte = 10^6 Byte
- GB = GigaByte = 1,000,000,000 Byte = 10^9 Byte
networks (your mileage may vary)
- modem : 56k bits/s (phone line)
- DSL : 3 Mbits/sec down, 0.8 Mbits/sec up
- i.e. my home "high speed internet" via phone line
- ethernet : 100 Mbit/s
- wireless : 10 Mbit/s
media
- CD = 700MB
- DVD = 4 to 7 GB
- iPod = tens of GB or more
- hard disk = 100GB or so
sizes of things
- text (and web pages)
- 1 page = 250 words at (say) (5 letters + space) = 1.5kB
- 1000 pages = 1.5MB (tiny by modern standards)
- image
- 8 bits each for red,green,blue = 24 bits/pixel
- 1000 x 1000 pixels, say, gives 3MB or so per image
- varies by dimensions and compression quality
- lossy jpg gives 30-ish times compression factor
- audio
- human hearing to about 30,000 cycles/sec = 30kHz
- bit rate various with quality, but about 192kbps is typical.
- 1 hour of audio = 3600 sec * 192 kb/sec = 90MB
- video
- varies a lot depending on size, quality, compression
- uncopmressed: 30 frame/sec * 640x480 pix * 24 bits/pix = 200 Mbit/s
- 1 hour uncompressed : 800 GB
- H264 or MPEG4 gives 1000 or so times compression (think 30x jpg, 30x time)
- ... bringing that to 0.8 GB or so
packets
- discuss briefly main idea of why that is better than dedicated channels.
- discuss LAN vs Internet, nesting of protocols
history
1962 SAGE - radar screen early warning
1969 RFC 1
1969 ARPANET : 2 computers in California
1978 X.25 first international packet network
1979 CompuServe offers dial-in email for PCs
1979 UUCP (unix-unix-copy) and usenet; ARPANET or X.25
1981 ARPANET : 213 computers across US
1981 UUCP : 550 computers
1982 SMTP (simple mail transfer)
1983 TCP/IP replaces NCP on ARPANET
1985-ish NSF, NASA, other governement agencies join
1985 IETF (internet engineering task force) starts
1986 NSFNet backbone established
1988-is first ISPs: PSINet and others
1989 HTML invented by Tim Berners-Lee
1990 300,000 internet hosts
1993 Moasic is first web browser from NCSA-UIUC
1992 NSF creates InterNIC to allocate addresses
1992 one million internet hosts; badwidh,cpu are 10^9,10^6 * 1962
1994 TCP/IP v4 - last big change
1994 Netscape Navigator browser
1995-ish search engines: lycos, webcrawler, yahoo
1998 IANA and InterNIC reorganized under ICANN
1998 google founded
2000 do-com bubble bursts
2004 MyDoom worm
2005 youtube.com
Following is from
08/81 213
05/82 235
08/83 562 x 2
10/84 1,024 x 2
10/85 1,961 x 2
11/86 5,089 x 2+
12/87 28,174 x 5
10/88 56,000 x 2
10/89 159,000 x 3
10/90 313,000 x 2
10/91 617,000 x 2
10/92 1,136,000 x 2
10/93 2,056,000 x 2
10/94 3,864,000 x 4
01/96 9,472,000 x 2.5
01/97 16,146,000 x 2
01/98 29,670,000 x 2-
01/99 43,240,000 x 1.5
01/00 72,400,000 x 1.5
01/01 109,600,000 x 1.5
01/02 147,300,000 x 1.3
01/03 171,600,000
01/04 233,100,000
01/05 317,600,000
01/06 395,000,000
01/07 433,200,000
01/08 541,700,000
Discuss : internet services today ?
old M'boro pages
... see attachments
![[paper clip]](/courses/source/wiki_images/paper_clip_tilt.png)
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